The group also called for the immediate resignation of Sheriff Lee Baca.

"Contrary to what the sheriff and his spokesperson contend, hundreds of inmates are telling the truth about deputy abuse," ACLU of Southern California legal director Peter Eliasberg said in a statement.

The ACLU, a court-appointed monitor of jail conditions, made its demands while releasing a 26-page report on jail conditions that included 70 sworn statements, including affidavits by two chaplains and a Hollywood producer who volunteer at the downtown Men's Central Jail.

"Sheriff Baca bears ultimate responsibility for the horrific details we uncovered compiling this report and must step down," Eliasberg said.

There was no immediate reaction from Baca, sheriff's spokeswoman Nicole Nishida said.

Michael Gennaco, who heads the County Office of Independent Review at the sheriff's department, planned to discuss the report during a news conference later Wednesday.

The ACLU said it received thousands of brutality complaints in the past year.

"I have never seen anything to match the institutional culture of deputy savagery," Margaret Winter of the ACLU's National Prison Project told a news conference.

"Hangover" producer Scott Budnick, a former jail writing tutor, chaplain Paulino Juarez and a second chaplain who submitted a statement anonymously said deputies brutalize inmates, and sheriff's supervisors don't take beating reports seriously.

Juarez said he was ministering to a Men's Central Jail inmate on Feb. 11, 2009, when he saw three deputies beating an apparently handcuffed inmate who was pleading for them to stop.

Gennaco said the chaplain's allegations aren't consistent with the investigation file.

The violence is systemic and not the work of a few rogue deputies, said Thomas Parker, the former assistant special agent in charge of the FBI's Los Angeles field office.

"Gang-like groups of deputies have been operating in the Los Angeles Sheriff's Department at least since the 1980s, and perhaps since the early 1970s, and these deputy gangs continue to operate today seemingly with impunity, right under the eyes of all levels of the current management," Parker wrote in the report.

The FBI has been investigating deputy conduct at county jails.

Eliasberg said U.S. Attorney General Eric Holder should order criminal and civil rights investigations into "deputy-on-inmate assaults, deputy-instigated inmate-on-inmate assaults and the regular use of excessive force inside the jail."

The demand came a day after Baca met with U.S. Attorney Andre Birotte to discuss an FBI undercover sting in which a deputy allegedly accepted about $1,500 to get a cell phone to an inmate who was an FBI informant.